Mayfly Species Leptophlebia intermedia (Black Quills)

A rather small species, distinguished from all others except B. grandis (now a synonym of L. intermedia) by the distinctive “scarf” type of penes.

Frontal margin of head red-brown; vertex and notum of thorax blackish. Sternum deep reddish black. Pleura dark red-brown with black markings. Fore leg red-brown (orange, in recently transformed specimens), tarsus slightly paler than femur and tibia. Venation orange to reddish brown; no stain at wing roots or in stigmatic area. Abdominal tergites dark red-brown, sternites more yellowish. Ganglionic areas orange; sternite 9 reddish brown. Usual pale oblique submedian streaks on tergites, dark markings at spiracles, and faint dark oblique submedian streaks on sternites. Middle tail fully 2/3 the length of the laterals. Tails dark red-brown, joinings obscurely darker. Penes much as in B. grandis, with the appendages extending backwards almost to end of notch (see fig. 138).

Described as B. grandis

Body length 11-13 mm, wing length 10-13 mm

This is a rather large species of lighter brown color, alternately yellowish brown. Thorax above shining brown with yellow streaks in the notal furrow each side. Legs dull yellow with the tarsi a little paler and the usual lines on the knee caps very narrow. Wings yellowish in front and toward the outer margin; hyaline at the center and toward the rear; hind wings white.

Abdomen pale yellowish brown, paler beneath especially in the middle of the segments. Segments 1 to 6 have the mid-dorsal pale line almost entire, and the paired oblique marks confluent with the pale rings at the base of the segments. The latter give the abdomen a distinctly ringed appearance. The dorsum of 7 to 10 brown, practically without color pattern. Tails white, distinctly ringed with reddish brown. Genitalia as in fig. 138.

This species is larger and paler than others of the genus; the ‘“scarf” type of penes is found only in this species and in B. intermedius (now a synonym of L. intermedia).